scholarly journals Cellulolytic Enzymes Production via Solid-State Fermentation: Effect of Pretreatment Methods on Physicochemical Characteristics of Substrate

2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Khushal Brijwani ◽  
Praveen V. Vadlani

We investigated the effect of pretreatment on the physicochemical characteristics—crystallinity, bed porosity, and volumetric specific surface of soybean hulls and production of cellulolytic enzymes in solid-state fermentation of Trichoderma reesei and Aspergillus oryzae cultures. Mild acid and alkali and steam pretreatments significantly increased crystallinity and bed porosity without significant change inholocellulosic composition of substrate. Crystalline and porous steam-pretreated soybean hulls inoculated with T. reesei culture had 4 filter paper units (FPU)/g-ds, 0.6 IU/g-ds β-glucosidase, and 45 IU/g-ds endocellulase, whereas untreated hulls had 0.75 FPU/g-ds, 0.06 IU/g-ds β-glucosidase, and 7.29 IU/g-ds endocellulase enzyme activities. In A. oryzae steam-pretreated soybean hulls had 47.10 IU/g-ds endocellulase compared to 30.82 IU/g-ds in untreated soybean hulls. Generalized linear statistical model fitted to enzyme activity data showed that effects of physicochemical characteristics on enzymes production were both culture and enzyme specific. The paper shows a correlation between substrate physicochemical properties and enzyme production.

2018 ◽  
Vol 8 (3) ◽  
pp. 424-431 ◽  
Author(s):  
Fernanda Castro Pires dos Santos ◽  
Joice Raísa Barbosa Cunha ◽  
Fábia Giovana Do val de Assis ◽  
Patrícia Lopes Leal

The adequate disposal of agricultural waste is one of the major concerns of public officials and a research challenge to obtain sustainable solutions to the problem. In this sense, the objective of this study was to evaluate the banana leaf stalk use as substrate in solid-state fermentation (SSF) for production of amylolytic and cellulolytic enzymes by Penicillium spp. LEMI A11 strain grown under different substrate concentrations, pH and temperature. Effects of different pH conditions (5.0 and 6.0), temperature (30 and 35 °C) and substrate concentration 70 and 90% (in relation to the final volume) of the fermentation were evaluated over 120 hours of fermentation. The results indicated that Penicillium spp. LEMI A11 was able to use the banana stalk as substrate under SSF. The maximum activities for amylase dextraining, amylase saccharifying and CMCase were 0.18; 0.13 and 04 U.g-1, respectively. The effect of environmental factors related to the substrate concentration was significant for saccharifying amylase and CMCase activity only. The interaction between the environmental factors tested was significant for the dextrinizing amylase activity only. It was verified enzyme activity reduction after 96 hours of fermentation for all enzymes. It concluded that banana stalk is an alternative carbon source to be used in SSF for enzyme production by of Penicillium spp. LEMI A11.


Biologia ◽  
2006 ◽  
Vol 61 (6) ◽  
Author(s):  
Figen Ertan ◽  
Bilal Balkan ◽  
Seda Balkan ◽  
Tulin Aktac

AbstractProduction of α-amylase from local isolate, Penicillium chrysogenum, under solid-state fermentation (SSF) was carried out in this study. Different agricultural by-products, such as wheat bran (WB), sunflower oil meal (SOM), and sugar beet oil cake (SBOC), were used as individual substrate for the enzyme production. WB showed the highest enzyme activity (750 U/gds). Combination of WB, SOM, and SBOC (1:3:1 w/w/w) resulted in a higher enzyme yield (845 U/gds) in comparison with the use of the individual substrate. This combination was used as mixed solid substrate for the production of α-amylase from P. chrysogenum by SSF. Fermentation conditions were optimized. Maximum enzyme yield (891 U/gds) was obtained when SSF was carried out using WB + SOM + SBOC (1:3:1 w/w/w), having initial moisture of 75%, inoculum level of 20%, incubation period of 7 days at 30°C. Galactose (1% w/w), urea and peptone (1% w/w), as additives, caused increase in the enzyme activity.


2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Hamid Mukhtar ◽  
Ikramul Haq

The present study describes the screening of different agroindustrial byproducts for enhanced production of alkaline protease by a wild and EMS induced mutant strain ofBacillus subtilisIH-72EMS8. During submerged fermentation, different agro-industrial byproducts were tested which include defatted seed meals of rape, guar, sunflower, gluten, cotton, soybean, and gram. In addition to these meals, rice bran, wheat bran, and wheat flour were also evaluated for protease production. Of all the byproducts tested, soybean meal at a concentration of 20 g/L gave maximum production of the enzyme, that is, 5.74  ±  0.26 U/mL from wild and 11.28  ±  0.45 U/mL from mutant strain, during submerged fermentation. Different mesh sizes (coarse, medium, and fine) of the soybean meal were also evaluated, and a finely ground soybean meal (fine mesh) was found to be the best. In addition to the defatted seed meals, their alkali extracts were also tested for the production of alkaline protease byBacillus subtilis, but these were proved nonsignificant for enhanced production of the enzyme. The production of the enzyme was also studied in solid state fermentation, and different agro-industrial byproducts were also evaluated for enzyme production. Wheat bran partially replaced with guar meal was found as the best substrate for maximum enzyme production under solid state fermentation conditions.


2016 ◽  
Vol 29 (1) ◽  
pp. 222-233 ◽  
Author(s):  
TAMIRES CARVALHO DOS SANTOS ◽  
GEORGE ABREU FILHO ◽  
AILA RIANY DE BRITO ◽  
AURELIANO JOSÉ VIEIRA PIRES ◽  
RENATA CRISTINA FERREIRA BONOMO ◽  
...  

ABSTRACT: Prickly palm cactus husk was used as a solid-state fermentation support substrate for the production of cellulolytic enzymes using Aspergillus niger and Rhizopus sp. A Box-Behnken design was used to evaluate the effects of water activity, fermentation time and temperature on endoglucanase and total cellulase production. Response Surface Methodology showed that optimum conditions for endoglucanase production were achieved at after 70.35 h of fermentation at 29.56°C and a water activity of 0.875 for Aspergillus niger and after 68.12 h at 30.41°C for Rhizopus sp. Optimum conditions for total cellulase production were achieved after 74.27 h of fermentation at 31.22°C for Aspergillus niger and after 72.48 h and 27.86°C for Rhizopus sp. Water activity had a significant effect on Aspergillus niger endoglucanase production only. In industrial applications, enzymatic characterization is important for optimizing variables such as temperature and pH. In this study we showed that endoglucanase and total cellulase had a high level of thermostability and pH stability in all the enzymatic extracts. Enzymatic deactivation kinetic experiments indicated that the enzymes remained active after the freezing of the crude extract. Based on the results, bioconversion of cactus is an excellent alternative for the production of thermostable enzymes.


2013 ◽  
Vol 4 (3) ◽  
pp. 201-209 ◽  
Author(s):  
José Manuel Salgado ◽  
Luís Abrunhosa ◽  
Armando Venâncio ◽  
José Manuel Domínguez ◽  
Isabel Belo

2013 ◽  
pp. 437-444 ◽  
Author(s):  
Aleksandar Knezevic ◽  
Ivan Milovanovic ◽  
Mirjana Stajic ◽  
Jelena Vukojevic

Species of the genus Trametes represent one of the most efficient lignin-degraders which can be attributed to a well developed ligninolytic enzyme system. Current trends are screening of ability of new species to produce these enzymes, as well as the optimization of conditions for their overproduction. Therefore, the aim of the study was to evaluate the potential of T. suaveolens to synthesize laccase and Mn-oxidizing peroxidases during fermentation of the selected plant raw materials. Level of enzyme activities was measured on 7, 10 and 14th day of submersion, as well as the solid-state fermentation of wheat straw and oak sawdust in the presence of NH4NO3 in previously determined optimal nitrogen concentration of 25 mM. The enzyme activity was determined spectrophotometrically using ABTS and phenol red as the substrates. The highest level of laccase activity (1087.1 U/L) was noted after 7 days of wheat straw solid-state fermentation, while during the submerged cultivation the production of the enzyme was not noted. Submerged cultivation in oak sawdust-enriched medium was the optimal for activity of Mn-dependent peroxidase (1767.7 U/L on day 14) and Mn-independent peroxidase (1113.7 U/L on day 7). Introduction of T. suaveolens to produce ligninolytic enzyme represented the base for further study, as well as the determination of relation between enzyme activity and rate of lignin degradation. It could lead to greater possibility of fungal species selection with high delignification capacity, which could take participation in sustainable production of food, feed, fibres, and energy, environmentally friendly pollution prevention, and bioremediation.


Sign in / Sign up

Export Citation Format

Share Document